By giving Peter Robinson "time out" to be with Iris and his family, the Democratic Unionist party may also be buying time for itself to assess the damage from one of the biggest scandals to rock Northern Irish politics.

In the six weeks while Robinson is no longer first minister, with Arlene Foster filling the post, the DUP will have space to analyse how much the controversy over their leader, his wife, her teenage lover and that £50,000 loan could cost the party electorally. At the end of this period, if there is no deal on the toxic policing issue, there could be elections for the 108-seat assembly – enough to focus the minds of politicians from every party.

The Guardian has learned that the DUP intends to conduct private polling, speak to its membership and test grassroots unionist opinion.

There will be one question on their minds: is the Robinson effect going to cost it more votes? It used to be one of the key elements of the DUP's rise, survival and triumph as the biggest unionist party.

For 28 years Peter Robinson stood at Ian Paisley's side quietly guiding the party the Big Man founded through talks, agreements, crises and several attempts at devolution. The East Belfast MP was the brains behind Paisley's populism.

Now the party will be gauging whether the revelations that his wife borrowed two sums of £25,000 each from property builders to set her 19-year-old lover up in business, allegations that her husband did not report this matter to parliamentary authorities, her attempt to kill herself and his decision hours later to address the Stormont parliament while she recovered, will have a severe impact on the DUP at the ballot box in May.

One Stormont insider said tonight: "If the feedback is negative, if the Robinson brand is shopsoiled then he might be spending more than six weeks with Iris and the family. The DUP might then conclude they would be better off with Arlene permanently."

Only Iris Robinson had a Westminster majority that seemed unassailable. Most of the nine seats the DUP holds in the Commons have majorities of between 4,000 and 5,000, which the Ulster Unionist/Conservative alliance will hope to challenge, and which they feel can be overturned if they surf a wave of anti-DUP revulsion.

As for the DUP's main political rivals, the Ulster Unionists have also been thinking about a post-Robinson future. One senior figure inside the Ulster Unionists told the Guardian todaythat even before the scandal broke the party had carried out private polling.

They claim the results left the UUP/Conservatives with 24 seats, the DUP down to 20 and Jim Allister's hardline Traditional Unionist Voice with eight. This outcome may entail Sinn Féin emerging as the largest single party and thus winning the right to nominate the post of first minister.

However, no unionist, DUP, UUP or TUV, member could survive politically if they agreed to serve under Martin McGuinness as first minister. The UUP strategist said the way around this dilemma was for his party and the DUP to act as a single unionist bloc. "If we can agree to a compromise candidate then the DUP and UUP will on the question only of the first minister act as one," he said.

This, of course, will happen only if Sinn Féin's frustration over the failure of unionists to devolve policing and justice powers results in republicans pulling out of the power-sharing arrangement. Sinn Féin has given the DUP a maximum of three of the six weeks Robinson stays out of office to resolve the policing issue.

In that period Sinn Féin wants assurances from the DUP that they are ready to transfer policing and justice powers from Westminster. If they believe the DUP are not serious about devolving them, Sinn Féin could use the need to renominate McGuinness as deputy six weeks from now as the date to bring the whole project crashing down.

In the middle of this unprecedented political drama it is worth remembering that a police officer remains critically ill, having been blown up in a dissident republican bomb attack last Friday.

For Sinn Féin, securing the devolution of policing and justice powers is critical in warding off any political threat from the dissidents. The continued failure to obtain that objective has been used by republicans opposed to the current compromise at Stormont to portray the system as dysfunctional and loaded in unionism's favour.

However, even if these powers were transferred it would not dissuade the Real IRA, Continuity IRA and Oglaigh na hEireann from "armed struggle".

Amid the furore at Stormont it went virtually unnoticed that one of the tasks Robinson has set himself in his six weeks "off" is to lead the behind the scenes negotiations with Sinn Féin.

Despite all his personal and political troubles Robinson remains an extremely able negotiator. Although he is taking a back seat on the backbenches, Robinson's backdoor talks with republicans could lead to the end of the deadlock between the two parties.

Even if he is forced to extend his "holiday" he could still walk away with the legacy that quietly, behind closed doors, he helped put in place the final piece in the devolution jigsaw.